Ket Exam

H&#304; everyone l was in England almost one year ago.I met my wife she is an English we got married in Turkey now we preparing to apply entry clearance visa so I have two questions could anyone help me please !!

1- l got my two certificates from my school in England which are "Advance CEFR C1 and BEC HIGHER ", are these certificates valid for Ket exam?

2-My wife is working but is not enough for £18600 to apply but have some saving. My question is that how long l need to keep this money on my account for ?